tesseract/cmake/AddCompilerFlag.cmake
2019-04-22 09:05:55 +02:00

131 lines
5.1 KiB
CMake

# - Add a given compiler flag to flags variables.
# AddCompilerFlag(<flag> [<var>])
# or
# AddCompilerFlag(<flag> [C_FLAGS <var>] [CXX_FLAGS <var>] [C_RESULT <var>]
# [CXX_RESULT <var>])
#=============================================================================
# Copyright 2010-2015 Matthias Kretz <kretz@kde.org>
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
# * Redistributions of source code must retain the above copyright notice,
# this list of conditions and the following disclaimer.
#
# * Redistributions in binary form must reproduce the above copyright notice,
# this list of conditions and the following disclaimer in the documentation
# and/or other materials provided with the distribution.
#
# * Neither the names of contributing organizations nor the
# names of its contributors may be used to endorse or promote products
# derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER AND CONTRIBUTORS ``AS IS''
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR
# ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#=============================================================================
get_filename_component(_currentDir "${CMAKE_CURRENT_LIST_FILE}" PATH)
include("${_currentDir}/CheckCCompilerFlag.cmake")
include("${_currentDir}/CheckCXXCompilerFlag.cmake")
macro(AddCompilerFlag _flag)
string(REGEX REPLACE "[-.+/:= ]" "_" _flag_esc "${_flag}")
set(_c_flags "CMAKE_C_FLAGS")
set(_cxx_flags "CMAKE_CXX_FLAGS")
set(_c_result tmp)
set(_cxx_result tmp)
if(${ARGC} EQUAL 2)
message(WARNING "Deprecated use of the AddCompilerFlag macro.")
unset(_c_result)
set(_cxx_result ${ARGV1})
elseif(${ARGC} GREATER 2)
set(state 0)
unset(_c_flags)
unset(_cxx_flags)
unset(_c_result)
unset(_cxx_result)
foreach(_arg ${ARGN})
if("x${_arg}" STREQUAL "xC_FLAGS")
set(state 1)
if(NOT DEFINED _c_result)
set(_c_result tmp0)
endif()
elseif("x${_arg}" STREQUAL "xCXX_FLAGS")
set(state 2)
if(NOT DEFINED _cxx_result)
set(_cxx_result tmp1)
endif()
elseif("x${_arg}" STREQUAL "xC_RESULT")
set(state 3)
elseif("x${_arg}" STREQUAL "xCXX_RESULT")
set(state 4)
elseif(state EQUAL 1)
set(_c_flags "${_arg}")
elseif(state EQUAL 2)
set(_cxx_flags "${_arg}")
elseif(state EQUAL 3)
set(_c_result "${_arg}")
elseif(state EQUAL 4)
set(_cxx_result "${_arg}")
else()
message(FATAL_ERROR "Syntax error for AddCompilerFlag")
endif()
endforeach()
endif()
set(_c_code "int main() { return 0; }")
set(_cxx_code "int main() { return 0; }")
if("${_flag}" STREQUAL "-mfma")
# Compiling with FMA3 support may fail only at the assembler level.
# In that case we need to have such an instruction in the test code
set(_c_code "#include <immintrin.h>
__m128 foo(__m128 x) { return _mm_fmadd_ps(x, x, x); }
int main() { return 0; }")
set(_cxx_code "${_c_code}")
elseif("${_flag}" STREQUAL "-stdlib=libc++")
# Compiling with libc++ not only requires a compiler that understands it, but also
# the libc++ headers itself
set(_cxx_code "#include <iostream>
#include <cstdio>
int main() { return 0; }")
else()
set(_cxx_code "#include <cstdio>
int main() { return 0; }")
endif()
if(DEFINED _c_result)
check_c_compiler_flag("${_flag}" check_c_compiler_flag_${_flag_esc} "${_c_code}")
set(${_c_result} ${check_c_compiler_flag_${_flag_esc}})
endif()
if(DEFINED _cxx_result)
check_cxx_compiler_flag("${_flag}" check_cxx_compiler_flag_${_flag_esc} "${_cxx_code}")
set(${_cxx_result} ${check_cxx_compiler_flag_${_flag_esc}})
endif()
macro(my_append _list _flag _special)
if("x${_list}" STREQUAL "x${_special}")
set(${_list} "${${_list}} ${_flag}")
else()
list(APPEND ${_list} "${_flag}")
endif()
endmacro()
if(check_c_compiler_flag_${_flag_esc} AND DEFINED _c_flags)
my_append(${_c_flags} "${_flag}" CMAKE_C_FLAGS)
endif()
if(check_cxx_compiler_flag_${_flag_esc} AND DEFINED _cxx_flags)
my_append(${_cxx_flags} "${_flag}" CMAKE_CXX_FLAGS)
endif()
endmacro(AddCompilerFlag)